Related Experiment Video
Updated: Jul 10, 2025

Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Exploring electronic and valley properties of single-layer SMSiN2 (M = Mo, W): a first-principles study on
Lijie Geng1,2, Kun Chen1,2, Hongyan Lu3
1School of Electronics and Information, Zhengzhou University of Light Industry, Zhengzhou, China. yyphysics@zzuli.edu.cn.
Abstract:
In this study, we employ first-principles calculations to explore the electronic and valleytronic properties of single-layer (SL) SMSiN2 (M = Mo, W), which are two-dimensional Janus materials with strong spin-orbit coupling. Our findings indicate that SL SMoSiN2/SWSiN2 possess a direct/indirect band gap, where the valence band maximum is situated at the K/K' point, giving rise to the formation of degenerate valleys. When considering spin-orbit coupling, SMoSiN2 and SWSiN2 demonstrate intriguing valley spin splitting in their valleys, with a maximum splitting of up to 0.14/0.39 eV in the valence bands. By implementing magnetic doping with V and Cr, we provide a demonstration that valley polarization could be realized in SL SMSiN2. Moreover, the findings reveal high carrier mobility in SL SMSiN2, notably in SWSiN2, where hole carriers can achieve a remarkable mobility of up to 7.98 × 103 cm2 V-1 s-1 along the zigzag direction. Furthermore, our observations suggest that strain can be effectively utilized to manipulate the character and magnitude of the band gap, as well as the valley spin splitting in these materials.
More Related Videos
Related Concept Videos
Band Theory
The energy difference between these bands is known as the band gap.
Conductor, Semiconductor,...
Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
Energy Bands in Solids
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
Molecular and Ionic Solids
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Electronic Structure of Atoms
An atom comprises protons and neutrons, which are contained inside the dense, central core called the nucleus, with electrons present around the nucleus. Taking into account the wave–particle duality of electrons and the uncertainty in position around the nucleus, quantum mechanics provides a more accurate model for the atomic structure. It describes atomic orbitals as the regions around the nucleus where electrons of discrete energy exist, characterized by four quantum...
Semiconductors
Metals such as copper (Cu), zinc (Zn), or lead (Pb) have low resistivity and feature conduction bands that are either not fully occupied or overlap with the valence band, making a bandgap non-existent. This allows electrons in the highest energy levels of the valence band to easily transition to the conduction band upon gaining...

